Clamping device



l. MATTSON.

CLAMPING DEVICE.

APPucATIoN man MAR. 1s. 1921.

1:4205725 A Patented June 27, 1922,

-llllllllmll A TTORIVEVS UNITED smrss gear JULrusfMATTsoN, or CHICAGO,j1traners.

cL'AivrrrNe nnvrcn'.

L To all wlzoimyz't may concern: f

Be it known that I, JULIUs MA'r'rsoN, a citizen of the United States, and a resident of the city f Chicago, in the county of Cook and State oflllinois, have invented va new and useful Improvement in VClamping Devices, of which the following is a full, clear,

and eXact description.

My invention relates to improvements in clamping devices and it consists in the combinations, constructions, and'arrangements herein described and claimed.

An object of my invention is to provide a device of the character described that embodies a'bolt and nut mechanism ofy novel construction.

A further obj ect of my invention is to pro' vide aclamping device embodying relatively movable means vadapted to engage with opposite surfaces ofthe work engaged so as to be locked in adjusted positions relative to one another and to'the work.

A further object of my invention is to pro-l vide a device of the character described in which a bolt'having ashank'adapted to be projected through registering -openings in lapped membershas ahead formed to en-y gage with an underlying Vsurface so as to lock the bolt in adjusted position relative to the lapped members when a nut is screwed -on the shank of the bolt to clamp the'lapped f lapped members toY one another, to lock theA head ofthe bolt in adjusted position relative to the lapped members, and to lock thel nut in adjusted position relative to the lapped members and on the shank of the bolt.

- A further object of'my invention is to providea device of the character described that is simple in construction, inexpensive to manufacture, and thoroughly practical com mercially.

. Other objects and advantages will appear in the following specification, and the novel positions, v o

' Figure Sis 'a plan viewofthe boltemf pointed out in theappen'ded claims.

ENT `armr1.5.;

Specification of Letters Patent; Jullie' 27; Application inea March 1e, '1921; Y i

My invention is illustrated ini. the accom# Panying drawings', forming partjof this applicatl'on, in which, f

`Figl'ire lis a section through lapped bers, showing the relativepositions of the;

bolt andnut clamping theV members to one another before the 7 nut has been fully tightened, Y j

' vFigure 2 is a view similar to Fig. l, showingthe parts of the device in operati-ve bodied in the device,

Figure 4 is a viewsimilar to Fig-2, showing vthe bolt used alone to securelapped members together, Figure 5 is a viewshowing the use and ap-` plication of armodified form ofthe device, a washer being embodied therein,

Figure Gis abo'ttom vplanxview of the washer embodied in the modified form of the device, and r i' f j Figure 7 is an edge View ofthe washer. 'In carrying out'my invention inits preferred forml provide a bolt comprising la shank lthreaded adjacent one end thereof,l

as at 2, and formed. integrally at its other end withy a head 3. The bolt may be formed of; Vany 1 suitable material having the krresiliency of the 4steel`usuallyused in the manu-k facture of bolts and the head thereof, which in` the vpresent instance is lshownas being square, may be round,heXagonal, or ofjany other desired form.' The head 3 is fashioned withafslot il in itsupper surface extending ventirely thereacross and intersecting the axis of the shank l. The under surface of the head 3 is formed to taperuniformly in opposite directionsfrom its median line paralljel with? the slot 4L so that relatively sharpV edges 5 and 6 are provided. f v

A nut? having a threaded bore 8 adapted to` engagewith the threaded portion 2 of thelshankA l is in yessential respects eX- actlyidenticalwith the head 3. A slot y9 in the upper surface ofthe nut corresponds` to the slot @while the under surface ofthe nut ,is taperedoppositely from its median line parallel with the slot 9 to s harpedges 10 and 11. j

From the foregoing description of the various parts of the device, the operationu thereof Vmay be readily'nnderstood. 'The shank l may. be projected through registerprovide the ing openings 12 and 13, respectively, in lapped members 14l and 15 so that the under surface of the head 3 contacts with the contiguous surface of the adjacent member. The nut 7 is then screwed on the threaded portion 2. Obviously, as force is applied to tighten the nut, the edges 5 and 6 of the head will 'grip' the surface engaged to prevent the turning of the head relative to the member 14. Consequently, the turning of the mit; will .clamp the. members 14 and 15 together more tightly, In the usual bolt and nutV construction, the head frequently turns; as the nut,V is screwed on the shank, thereby rendering the turning of the nut ineffective. As the nutis screwed on the shank more tightly against the contiguous surface ofthe member 15, the edges 10 ant 1l will engage with` the surface contacted. Continued tightening of Ythe nut 7 tends to move the opposite side portions of the head' 3 and of the nut 7 about their respective median lines so that the upper edges of the slot. 4 'are moved slightly toward each other as shown in Figure 2 andthe corresponding edges of the slot; 9` are likewise moved slightly toward one another, as shown in the same figure. Obviously, this movement will be, resisted onaccount' of the resiliency Vof the material composing the. head and the nutand consequently the head 3' and the nut 7 will be locked in adjusted positions relative to the members 14and 15 as the edges 5 and 6 and 10 and 11 will be constantly maintained inoperative engagement with the contiguous surfaces. ln addition, the nut 7 will be l'ockedin. adjusted position relativeto thev threaded portion of the shank Las, the thrustagainst the edges 10 and 11 causes the opposite walls of the slotted portion ofthe bore 8 to be moved toward one another and thus forced tightly against the threaded` shank.,

It will beobserved that the nut 7 and' the head 3 are adapted to beengaged by either awrench or a screw driver.

Referring now toy Figure 4, I show a modified form of the` device in which a-bolt of the cap screw type is provided. The bolt in this modified form. of the invention comprisesA a shankx20 thatis threadedfor its entire length and ahead 21 that is identical in essentiall respects with the head 3 of the preferred form of the device,` being provided' with ar slot 22 in its upper surface and having its under surface formedto provide opposite sharp edges 23 and 24. It will be lnoted that no nut is used in this embodiment, of the invention as the threaded shank made of wood or other relatively soft mate-V same reference numeral is mounted on the shan-k 1 betweenthe nut 7 vand the contiguous surface of the member 33. One surface of the washer 34viseorrugated ask at 35 and I this corrugated surface contacts withthe contiguous surface of the member engaged, thereby preventing movement of the washer relative to the surface of the member rengaged.V rlhe washer embodied in this modifi'- cation of the invention is clearly shownl in `Figures 6 and 7. The sharp; edges 5y and 6 of the head and 10 and 11 of the nut engage` the upper surfaces of the underlying washers so the operation of the modified form of the device illustratedin Fig. 5 is in essential respects identical with the operation of the preferred form of the-device. lf the sharp. edges 5 and 6 of the head` and 10 and 11 of the nut were ,movedv intocontact with thev surfaces of thel relatively soft m-ateri-ahsuch as that forming the'niembers' 32 and 33, it is4 possible that annular grooves would be cutin the surfaces contacted, thereby detrimentally affecting the operationl of the device. The washers 34 are` therefore interposed in the manner described and illustrated. y

y It will be understood that many forms and modications of the device other thanthose illustrated may be provided. without departing from the spirit yand scope of my invention as set forth in the-foregoing disclosure and outlinedl more particularly in the appended claims, and 1 therefore considersuch modifications and adaptations as my own.

I claim:

1. ln a device-of the character described,A a bolt formed with a head having a slot iny its upper surface and having its under surface formed to Contact with a contiguous surface along the opposite edges thereof par-- allel withthe slot, whereby thehead ismaintained in adjusted position when clamped to the underlying surface. g 1

2. The combination with lapped mein-bers having registering` openings therethrough of a bolt having integral head and shank portiops, said shank being threaded adj acent. its ent threaded openings and said head Vbeing formed with a diametrically disposed slot in its upper surface and with its under surface tapering uniformly in opposite directions from'its median line parallel with the slot to the edges thereof, and means engaging with the threaded portion of the shank and with the adjacent surface of one of the lapped members for clampingthehead to and being projected through saidY the opposite surface of the other of the lapped members, whereby the lapped members are clamped together and the head is maintained in adjusted position. 3. The combination with lapped members having registering openings therethrough of a bolt having integral head and shank portions, said shank being threaded adjacent its end and being projected through said threaded openings and said head being formed with a diametrically disposed slot in its upper surface and with its under surface tapering uniformly in opposite directions from its median line parallel with the slot to the edges thereof, and a nut screwed on the threaded portion of the shank for engaging with the adjacent one of the lapped members and for clamping the head'to the opposite surface of the other of the lapped members, said nut having a diametrically disposed slot in its upper side and having its under surface tapering uniformly in opposite directionsfrom the median line thereof parallel with the last named slot, whereby the head and the nut are clamped in adjusted positions to opposite surfaces of the lapped members andthe nut is locked to the shank. 4. The combination with lapped members having registering openings therethrough of a bolt having integral head and shank portions,said shank being threaded adjacent its end and being projected through said threaded openings and said head being formed with'a diametrically'disposed slot in its upper surface and with its under surface tapering uniformly in opposite directions from its median line parallel with the slot to lthe edges thereof, a'washer disposed on the shank between the head and the adjacent one of the lapped members, said washer being formed with its vunder surface corru-rv gated to grip the surface of the contiguous member, and a nut screwed on the threaded portion of the shank to engage with the adjacent one of the lapped members, whereby vface of the head is moved into engagementat opposite edges thereof with the surface provided with the threaded opening in which the shank is screwed and the head is thus maintained in adjusted position relative to the work.

' JULIUS MATTSON. 

